


Children of the Sea

by SilverWolf2135



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: F/F, Fluff, Mermaids, Minor Spoilers, Soulmates, This is just an excuse for a grown man to make a mermaid fanfiction, True Love, so come at me
Language: English
Status: In-Progress
Published: 2020-02-23
Updated: 2020-06-06
Packaged: 2021-02-28 06:07:38
Rating: Not Rated
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 2,163
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22869097
Author URL: https://archiveofourown.org/users/SilverWolf2135/pseuds/SilverWolf2135
Summary: Dorothra and her wife Petra go for a swim in the setting sun's orange glow
Relationships: Dorothea Arnault/Petra Macneary, Edelgard von Hresvelg/My Unit | Byleth, Minor or Background Relationship(s)
Kudos: 26





	1. Chapter 1

**Author's Note:**

> So my first Three houses fanfic, and it's mermaid story staring my favorite Black Eagles ship. Who cares, Mermaid DoroPetra.  
> Also minor spoilers of the Crimson Flower route. Enjoy

Dorothea looked outwards towards the sea, as the sunset. She knew that to the east of where she was standing was the Imperial capital Enbarr, home to Emperor Edelgard and her old professor, Byleth. Ever since defeating The Immaculate One over 3 years ago, peace in Fodlan had returned. Although, she couldn't help but think about those who lost their lives in the war. Edelgard was kind enough to spare Claude when they attacked Derdriu, and Hilda ended up returning to her home after the war was over, to ensure Almrya didn't launch any surprise attacks on the new Adretisian Empire. However, other people weren't so lucky.  _ “ _ Dedue and Dimitri were both killed when Dimitri refused to surrender, Cyril and Catherine both followed Rhea to the death, and Annete had lost her own father during the final battle. Everyone lost someone, and everyone mourned who they lost.

With the war with the Church of Serios and the Kingdom over, and Hubert taking the charge in the war against Those who slither in the dark, Dorothea knew she could leave Fodlan in good hands. After all, it wasn't long after Byelth and Edelgard announced their marriage that Dorothea and Petra announced theirs. Edelgards and Byelth's wedding was held in Enbarr, with Dorothea and Petra having theirs in Brigid. Everyone, even Edelgard, Hubert, and Byelth came to see the wedding. Even Claude came to give his congratulations on their marriage, and even gave Dorothea an Almyrain ring, rumored to grant the wish of whoever holds it.

Dorothea was finally happy. With the love of her life at her side, Fodlan at peace, and Edelgard in the middle of negotiating with Almyra, things couldn't seem to get any better. Dorothea made her way down to the beach near the palace. While nowhere near as grand or refined as the imperial palace, the Palace of Macneary was still an impressive building. Big enough to be a castle by Fodlan standards, it had a warm and cozy interior, with animal hides in every room, pleasant smells coming the kitchen on every floor, and the morning and setting sun bathing every room in a warm orange glow, it was everything most Fodlan castles and palaces weren't. Although Dorothea still wore dresses from Fodlan, she had to admit that the dresses and clothes of Brigid held a charm to them, a charm that her wife always seemed to bring out.

* * *

Petra had ascended the Bigirdai throne shortly after returning to Brigid. Although this was soured by her grandfather's passing. Although Dorothea had only met him a handful of times, she could see that he loved Petra, and once Petra and Dorothea were wed, he performed a ritual to give the couple his blessing as well as the Blessings of Brigid. After he had passed, Petra took the crown, and while the death of her grandfather weighed heavily on her mind and heart, Dorothea was always there for her, comforting her when Petra began to doubt herself, or when thoughts of her grandfather brought her to the brink of tears, Dorothea was always there for her wife.

Petra looked at the sea water as the waves crashed into the sand, barely reaching her feet. Ever since returning home, Petra and worked herself to the bone to improve relations with the Empire. Thankfully, Ferdinand made the process easier, as he had great favor over the people of Fodlan. And while they still had a long way to go, Petra was hopeful that one day, Brigid and Foldan would be equals, and there would be no threat of war looming over their heads. Her marriage to Dorothea had helped a great deal as well. Brigid was far more accepting of same sex marriages then Fodlan, with everyone in Brigid being encouraged at a young age to experiment with their sexuality. Thanks to advancements in medicine and magic(or so her wife told her, as magic was even harder for her then speaking English, what Dorothea said was the main language of Fodlan) it was possible for a same sex couple to bear children.

“ _ Want to go for a swim? _ ” Petra smiled as Dorothea wrapped her arms around. Dorothea took to learning the native Brigid language and had become very fluent in Brigidai in the 3 years they had been together. And while Petra’s English still had room for improvement,it was still vastly better than her academy days. “ _ Not today. The water is too cold. _ ” Dorothea couldn’t help but laugh. “ _ After all we’ve been through, you're still going to whine about the water here being cold? Maybe we should go back to Faerghus for a bit? _ ” Petra shuddered at the memory of how bitterly cold it was during the final battle in Fhirdiad. Despite the whole city in flames, a cold wind still chilled everyone to the bone, Petra more than anyone else in the Black Eagle Strike Force. “ _ On second thought, maybe it’s not so cold. Do you want to come with me? _ ”

Dorothea and Petra stripped themselves of their clothing and waded into the warm water of Brigid. Dorothea could never get over how warm it was, compared to everywhere she had been in Fodlan, this water was as warm as a bath. And she loved it. Ever since coming to Brigid, she had come to love swimming in it’s waters. Bathed in the evening glow of the setting sun, she felt like she was mermaid, a creature of myth that she had read about during her academy days. Dorothea was surprised to learn that Brigid also knew of mermaids, only they called them sirens. Petra even told Dorothea that her grandfather once told her a story of how her ancestor help a dying mermaid, and in return, the mermaid promised them a chance to become “A Child of the Sea”

  
“ _ You look so beautiful my love. If only we could live out this day forever. _ ” Dorothea smiled and kissed her wife, letting the warm waters of her new home envelope her and her lover.


	2. Chapter 2

**Summary for the Chapter:**

> In the warm morning sun, Dorothea and Petra receive a letter from the emperor herself

**Notes for the Chapter:**

> Wow. was not expecting this to blow up like it did. Glad to see someone people are as interested in this as i am. Here's another chapter for you

As the orange glow of the morning sun filled the room, Petra could feel herself being pulled away from her peaceful slumber. She looked down to see her wife sleeping peacefully in her arms. As the warm breeze blew in through the window, Petra thought back to their swim last night. Such moments were very rare, as her duties as Queen often kept her from her loving wife. There were days when all Petra wanted to do was retire to her room and snuggle with her lover, or go for a relaxing swim, like they had the day before. The longer they swam, the less they wanted to return to the castle.

As Petra pondered her thoughts, she felt Dorothea awaken, feeling Dorothea’s arms tighten around her waist. “ _Good morning my love. How long have you been up?_ ” Petra couldn’t help but laugh. Leave it to her wife to treasure every second they had together, as if Petra would leave her. “ _Good morning my beloved. I awoke only moments ago. I was just thinking._ ” Dorothea giggled. “ _You're always thinking. Maybe I need to purge your mind of all those troubling thoughts._ ” Petra smiled as she and Dorothea kissed, preparing to give her wife the best pleasure she had ever felt, when they heard a knock on the door. 

“ _Your Grace, forgive me. A letter from Emperor Edelgard just arrived. It’s addressed to you in our tongue_ .” Both Dorothea and Petra were surprised at this news. It had only been a week ago that Edelgard had sent word requesting their presence at a conference in Enbarr three moons from this one. If Edelgard wrote to them again in such a short time, it must be important. As Petra dressed herself and opened the door, the Hand of the Queen handed her a letter, written in Brigidai and sealed with the coat of arms of the Empire. “ _Thank you Master Alloan. Have a messenger owl ready.”_ As Petra closed the door, she walked back to her wife and bed, wondering what would cause Edelgard to write in a language that was not her own. As Petra opened the letter, Dorothea moved closer so she could read it as well. Thanks to her own studies and Petra’s help, she could fully read the letter, but that didn’t make the contents any less shocking.

“ **My dearest friends, I pray that this letter finds its way to your hands, for the contents of this letter are for your eyes only. Dorothea, you know of the legend of the Mermaid, a being that is found in tropical water and is too beautiful to be considered of this world. Petra, you’ll have heard a similar tale, only you would know them as Sirens. Well, travellers have reported seeing mermaids near Brigid, and they fear that they may be in danger, because of the number of battleships that were in the sea not too long ago. I would normally see to this myself, however matters of court and the civil unrest due to a nobles rebellion leave me with no choice but to stay here to deal with this nonsense. So I request that you two investigate this for me and report what you find. I’ve made arrangements with a trader currently on his way to Brigid with spices and clothes from Fodlan. After he is done trading, he is to lead you two to the cove that the sailors report seeing these mermaids often. A cove called the Blue Pearl. I thank you for aiding me with this matter. I hope the next time we see each other will be under happier terms.**

**Best regards, El.**

  
  


Dorothea and Petra looked at each other and back at the letter. “It seems as though we have a mission my love”


	3. Chapter 3

**Summary for the Chapter:**

> Dorothea and Petra prepare to enter the cove, despite feeling uneasy and nervous about the adventure

**Notes for the Chapter:**

> Hello everyone. Sorry for not posting a new chapter in a long time. Here's a short chapter to set up a much longer chapter that will be out before the month is over. Enjoy it, and leave a comment on how you think I'm doing with this story

“Are you sure this is the place? It looks like there’s nothing here.”

The captain nodded. “I followed the directions Her Majesty gave me, kept the sun on the East side for a day, and followed the moon’s glow for half a night. This has to be it.”

Dorothea looked around some more. While this place was nothing special, she could feel something. Something was pulling her towards the rocks near the shore. The cove at first glance seemed to be just another average cove, with a decent sized cave at the center of it all. If Dorothea remembered the legends right, mermaids like to be in coves with some kind of cave system. Whether or not this is true, she and Petra were about to find out.

Dorothea would be lying if she said she wasn’t nervous. While Petra and herself were among the best fighters during their Black Eagle Strike Force days,however that was a long time ago, and since the peace treaty between the Empire and Brigid, there was no need for Petra or Dorothea to keep fighting. While there was the occasional run in with a Demonic Beast that needed their intervention, those were so rare. While they did bring high quality silver weapons with them and was even able to convince Ingrid to send them the sword Mercurius for Petra to use , Dorothea wondered if it would be enough to protect themselves.

* * *

Petra was unsure of what to think of this place. Before she was shipped off to Fodlan as a glorified prisoner of war, she had gotten to know the coves and isles surrounding Brigid, and yet she had never heard of the place. Stranger still was that supposedly, this cove was in between Brigid and Dagda, an area that both Petra and Shamir knew well enough. Before setting off, Petra had written a letter to Shamir, to ask for her input on the rumors surrounding the sirens, and what Shamir wrote was both confusing and unhelpful

While Brigid and Dagda shared many legends and customs, Shamir claimed that Dagda had no legends about sirens, or any other sea dwelling creature. Shamir admitted that it’s possible for sirens to exist and have no one know about them, but also admitted to not having much faith in legends and rumors regarding anything she can’t see or feel herself.

Petra wasn’t sure what to make of Shamir’s letter. While Shamir wasn’t the type of person to lie to anyone, Brigid and Dagda had been close for hundreds of years, so the idea of Shamir not at least hearing about sirens was odd. Still, Edelgard had asked them to look into this, and look into it they will. Petra grabbed her axe, her bow, and Mercurius and prepared to explore the cave before them.

  
“Wait two days for us. If we are not back by then, assume the worst.”

As Dorothea and Petra entered the cave they failed to notice the 2 women in the water watching them enter the cave. As Petra and Dorothea disappeared into the dark cave, the two mysterious women disappeared into the water, with a splash.


End file.
